“Software is the invisible thread and hardware is the loom on which computing weaves its fabric, a fabric that we have now draped across all of life”.

Grady Booch

Software, although an “invisible thread” has certainly had a significant impact on our world and now pervades pretty much all of our lives. Some software, and in particular some software architectures, have had a significance beyond just the everyday and have truly changed the world.

But what constitutes a world changing architecture? For me it is one that meets all of the following:

1. It must have had an impact beyond the field of computer science or a single business area and must have woven its way into peoples lives.
2. It may not have introduced any new technology but may instead have used some existing components in new and innovative ways.
3. The architecture itself may be relatively simple, but the way it has been deployed may be what makes it “world changing”.
4. It has extended the lexicon of our language either literally (as in “I tried googling that word” or indirectly in what we do (e.g. the way we now use App stores to get our software).
5. The architecture has emergent properties and has been extended in ways the architect(s) did not originally envisage.

Based on these criteria here are five architectures that have really changed our lives and our world.

World Wide Web
When Tim Berners-Lee published his innocuous sounding paper Information Management: A Proposal in 1989 I doubt he could have had any idea what an impact his “proposal” was going to have. This was the paper that introduced us to what we now call the world wide web and has quite literally changed the world forever.

Apple’s iTunes
There has been much talk in cyberspace and in the media in general on the effect and impact Steve Jobs has had on the world. When Apple introduced the iPod in October 2001 although it had the usual Apple cool design makeover it was, when all was said and done, just another MP3 player. What really made the iPod take off and changed everything was iTunes. It not only turned the music industry upside down and inside out but gave us the game-changing concept of the ‘App Store’ as a way of consuming digital media. The impact of this is still ongoing and is driving the whole idea of cloud computing and the way we will consume software.

Google
When Google was founded in 1999 it was just another company building a search engine. As Douglas Edwards says in his book I’m Feeling Lucky “everybody and their brother had a search engine in those days”. When Sergey Brin was asked how he was going to make money (out of search) he said “Well…, we’ll figure something out”. Clearly 12 years later they have figured out that something and become one of the fastest growing companies ever. What Google did was not only create a better, faster, more complete search engine than anyone else but also figured out how to pay for it, and all the other Google applications, through advertising. They have created a new market and value network (in other words a disruptive technology) that has changed the way we seek out and use information.

Wikipedia
Before WIkipedia there was a job called an Encyclopedia Salesman who walked from door to door selling knowledge packed between bound leather covers. Now, such people have been banished to the great redundancy home in the sky along with typesetters and comptometer operators.

If you do a Wikipedia on Wikipedia you get the following definition:

Wikipedia is a multilingual, web-based, free-content encyclopedia project based on an openly editable model. The name “Wikipedia” is a portmanteau of the words wiki (a technology for creating collaborative websites, from the Hawaiian word wiki, meaning “quick”) and encyclopedia. Wikipedia’s articles provide links to guide the user to related pages with additional information.

From an architectural point of view Wikipedia is “just another wiki” however what it has bought to the world is community participation on a massive scale and an architecture to support that collaboration (400 million unique visitors monthly more than 82,000 active contributors working on more than 19 million articles in over 270 languages). Wikipedia clearly meets all of the above crtieria (and more).

Facebook
To many people Facebook is social networking. Not only has it seen off all competitors it makes it almost impossible for new ones to join. Whilst the jury is still out on Google+ it will be difficult to see how it can ever reach the 800 million people Facebook has. Facebook is also the largest photo-storing site on the web and has developed its own photo storage system to store and serve its photographs. See this article on Facebook architecture as well as this presentation (slightly old now but interesting nonetheless).

I’d like to thank both Grady Booch and Peter Eeles for providing input to this post. Grady has been doing great work on software archeology  and knows a thing or two about software architecture. Peter is my colleague at IBM as well as co-author on The Process of Software Architecting.